Background: Several studies have outlined a possible relationship between an increased body mass index (BMI) and respiratory allergic diseases, such as asthma and rhinitis. The aim of the study was to analyse the relationship between BMI and allergic diseases, including allergic rhinitis and asthma, and functional parameters, such as nasal airflow, FEV(1), and non-specific BHR to methacholine, in a cohort of navy army subjects.
Methods: The study included 100 patients with moderate-severe persistent allergic rhinitis alone, 100 with intermittent allergic asthma alone, and 100 healthy controls. All subjects were evaluated performing skin prick test, spirometry, and bronchostimulation test with methacholine. Rhinomanometry was performed in patients with rhinitis.
Results: BMI values were significantly lower in control subjects with respect to patients with rhinitis (P=0.0002) and with respect to patients with asthma (P<0.0001). BMI was also significantly higher in males with respect to females (P=0.005). A significant relationship has been observed between some categories of BHR and BMI either in patients with rhinitis (P<0.01) or in patients with asthma (P<0.01), whereas there was no association between BMI and functional parameters.
Conclusion: This study provides the first evidence of a significant relationship between BMI and allergic rhinitis and between BMI and BHR in both allergic disorders.